Abstract
BackgroundHealth-care professionals need to collect wound samples to identify potential pathogens that contribute to wound infection. Obtaining appropriate samples from diabetic foot ulcers (DFUs) where there is a suspicion of infection is of high importance. Paired swabs and tissue biopsies were collected from DFUs and both sampling techniques were compared using 16S rRNA gene sequencing.ResultsMean bacterial abundance determined using quantitative polymerase chain reaction (qPCR) was significantly lower in tissue biopsies (p = 0.03). The mean number of reads across all samples was significantly higher in wound swabs Big(overline{X} = 32,014) compared to tissue ( overline{X} = 15,256, p = 0.001). Tissue biopsies exhibited greater overall diversity of bacteria relative to swabs (Shannon’s H diversity p = 0.009). However, based on a presence/absence analysis of all paired samples, the frequency of occurrence of bacteria from genera of known and potential pathogens was generally higher in wound swabs than tissue biopsies. Multivariate analysis identified significantly different bacterial communities in swabs compared to tissue (p = 0.001). There was minimal correlation between paired wound swabs and tissue biopsies in the number and types of microorganisms. RELATE analysis revealed low concordance between paired DFU swab and tissue biopsy samples (Rho = 0.043, p = 0.34).ConclusionsUsing 16S rRNA gene sequencing this study identifies the potential for using less invasive swabs to recover high relative abundances of known and potential pathogen genera from DFUs when compared to the gold standard collection method of tissue biopsy.
Highlights
Health-care professionals need to collect wound samples to identify potential pathogens that contribute to wound infection
These results are in contrast with a study by Dunyach-Remy et al, (2014) using polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) [24], whereby significantly greater proportions of known pathogens were identified in diabetic foot ulcers (DFUs) tissue samples (87%) compared to swab samples (58%), with no pathogenic bacteria detected in 9 of the 20 swab samples
Using 16S rRNA gene sequencing, this study has investigated the concordance of paired swab and tissue biopsy samples from diabetic foot ulcers
Summary
Health-care professionals need to collect wound samples to identify potential pathogens that contribute to wound infection. Obtaining appropriate samples from diabetic foot ulcers (DFUs) where there is a suspicion of infection is of high importance. Damage to the protective skin envelope enables entry of microorganisms which colonise host tissue. This may lead to further microbial replication and damage to host tissue which can manifest as a clinical infection [2]. The colonisation of microorganisms may lead to a stable microbial community, which does not elicit a host response, but contributes to several ill-defined mechanisms keeping the wound in a “chronic” non-healing state [3]. Accurately identifying the microbiome within DFUs could enhance treatment by enabling targeted therapeutic regimens, which include the use of systemic or topical antimicrobial therapies in order to augment sharp debridement
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call